Ask HN: Quiet/cheap study havens around San Francisco?

So I'm planning on going to SF soon (coming from O/S) for a job interview. The only problem is I have to get into the US a couple of weeks earlier to present some research at a conference in Wisconsin, and am at a bit of a loss as to what to do with the time in between. I really just want to find a quiet place to study up on Coursera so that I'm fully prepped for the interview, and to just make good use of the time.

Can anyone think of somewhere to stay that's quiet and not too expensive (and accessible by public transport)? Eg. a decent cabin in a caravan park or something like that. The closer to SF the better but it's not an absolute requirement, I guess technically it could be anywhere between Wisconsin and California. Doesn't have to be anywhere touristy. My plan otherwise was to just hang out at the Hayes Valley inn for that duration, but it seems like an expensive way to spend all day on the computer! Airbnb would also be an option I guess (can be risky tho...).